The broad objective of this research project is to gain some insight into the biochemistry and metabolic processes of marine organisms, especially primitive forms. Attention is presently focused on the horse shoe crab, Limulus Polyphemus. Current inrestigations deal with: 1. Isolation and identification of the numerous pigments present in Limulus eggs. 2. Identification of the pigment responsible for the color of the red or coaxal gland and the function of this gland.